using 'global' across source files.

[Bram Stolk]

Mark Jackson wrote:
> 
> Bram Stolk <bram at sara.nl> writes:
> > According to the manuals, it should simply be in the namespace
> > '__main__', but that doesnt work either.
> 
> You're misreading the manuals.  Can you tell us how you drew this
> conclusion?  (Possibly the manuals could be clearer.)

Well, because in execframes.html, it can be read that:
"The main module for a script is always called __main__"

And because I can do:
dir(__builtins__)

I thought, why the heck doesn't dir(__main__) work?
I also tried dir(__mains__), dir(main), etc.

Now I know, (thx Remco) that I first have to map the string 
__main__ to a module using sys.
This could be in the ref manual. I think it is not in
there currently.


Also, I had no idea that using a 'global val' cmd, creates 
another copy of val, which I deduct from your comment:
"But the val that change_val changes is defined in funcs.py, 
NOT prog.py"

I thought that python's 'global' acted like C's 'extern' cmd,
meaning, that 'global val' does NOT define/create 'val',
only refers to a val that exists somewhere else.

I don't know wether me thinking this is due to my poor
understanding, or the quality of the manuals, though.


Anyway, to clear things up: what I wanted to achieve is
pretty straightforward: I can use "global vars" that
reside outside a func body, but in the same module.
I wanted one step further: use "even more global vars"
that reside outside a func body, and even outside the
current module (read: sourcefile).

I can achieve this now, with the sys lookup of __main__.
(Provided ofcourse that __main__ is the module that
 holds the req'd variable).

I thought that the subject line that I had chosen
"using 'global' across source files" summed up my
problem pretty accurate. But appearantly it did not ;-)



   Bram


> 
> --
> Mark Jackson - http://www.alumni.caltech.edu/~mjackson
>         The power of accurate observation is frequently called
>         cynicism by those who don't have it.
>                         - George Bernard Shaw

-- 
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 Bram Stolk, VR Specialist.
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